From this beautiful book, God For Us: Rediscovering the Meaning of Lent and Easter, I learned some interesting tidbits about traditions surrounding the Fifth Sunday of Lent.
In the Eastern Orthodox tradition, this Sunday is observed as a holy day honoring Saint Mary of Egypt (AD 344-421). For many Christians, St. Mary is the patron saint of penitents. During Lent, a year before her death, she encountered a priest in the desert and asked him to return the following year so she could receive communion. The priest returned on Holy Thursday, and just before dying, Mary received the sacrament for which she had waited.
In God For Us, Beth Bevis says, "The placement of Mary's saint day near the end of Lent provides an opportunity to reflect on the parallels between Lent and the life of a saint." If we are weary of our Lenten acts of penance, we can be encouraged by what awaits us at the end of our journeys, just as St. Mary was.
In the UK, this Sunday is known as "Carling Sunday" after the dried peas (carlings) that were traditionally served on this day. That tradition stemmed from an old English church custom of distributing beans to the community due to the scarcity of food at midwinter. The Fifth Sunday in Lent was also known as Passion Sunday until 1969, marking the beginning of the Passiontide as a two week journey. As we do now in one week, "the church turned its attention to the love that inspired Christ to suffer on behalf of humankind."
Even though our liturgical observation of the Passion does not begin until next Sunday with Palm Sunday, it is fitting that we begin to turn our hearts towards Christ's journey to Jerusalem, "anticipating with greater urgency the coming events of Christ's death and Resurrection."